How many times it happened to you that your phone battery just went flat and there is no charger anywhere near you?
Phones get faster every year, but battery life doesn’t seem to get any better. If you need to keep your smartphone – or tablet or other USB-powered device – going all day, you need a power bank. Power bank serve as an ‘extra battery’ or external charger for your phone or other electronic devices.
Power banks come in all shapes, weights and capacities, from emergency credit-card-sized devices such as the Onaji Pawa that offers a quick boost to keep you going until you get home, to the ultra-high-capacity LimeFuel Blast Pro L240X, which might charge your phone in excess of 10 times – ideal if you’re going camping or have several devices to charge. Then there are those able to recharge their own battery using solar power, which could mean you never need charge your devices using mains power again. That could save you a few quid on the electricity bill – if you have the patience.
Choosing a power bank
Several factors are important when choosing a power bank. One is portability: some of the power banks are small and light enough to slip into a pocket; others you’ll notice their presence even when slung in a bag. Pay particular attention to their weight and avoid bulky designs if this is a device you’ll carry every day, rather than in certain situations only.
Another factor is capacity. It’s important to note that a power bank will not deliver its full advertised capacity to your device – some of this energy is lost through heat generated and voltage conversion. If a power bank manufacturer doesn’t expressly state otherwise, expect to achieve around 70 percent efficiency. A 10000 mAh power bank might therefore deliver 7000 mAh of power. Some of the best power banks offer around 90 percent efficiency. Check the specification of your phone or tablet’s battery to estimate how many full charges you can expect from this.
A 12000 mAh REAL CAPACITY power bank, able to charge a 1500 mAh capacity phone for 8 times full?
This is a common mistake make by most of the people. For rough calculation of the total charge time, kindly use this formula:
REAL CAPACITY * conversion rate * phone battery health / phone capacity = total charge times
EXAMPLE: 12000 x 0.8 x 0.8 / 1500 = 5.12 charge times (0.5-1 times plus minus)
What’s conversation rate?
Conversation rate is the remaining percentage of the battery after the battery lost in heat or PCB operation.
What’s phone battery health?
In simple, it’s mean how‘healthy’ your phone battery is. Phone battery storage capacity will be lower and lower. That’s also the reason why our phone can last longer when it’s newly bought than after 3-6 months we used it. Different mobile phone models also will affect the calculation as some phone drain battery faster than the other.
The ideal power bank carefully balances useful capacity with portability, value, fast charging/recharging, multiple outputs and high-end features such as passthrough charging and LCD displays.